SAN FRANCISCO (CBS/AP) — An Oakland medical marijuana dispensary that’s been billed as the largest pot shop on the planet is being targeted for closure by federal prosecutors in Northern California.

Harborside Health Center spokeswoman Gaynell Rogers said U.S. Attorney Melinda Haag’s office has threatened to seize the property where the popular dispensary has operated since 2006 as well its sister shop in San Jose.

Rogers said employees found the complaints taped to doors at the two locations on Monday.

Although medical marijuana is legal in California, court papers filed Sunday said the dispensaries were violating federal law by selling marijuana.